Feather Stars (Crinoids)
These starfish are magnificent to look at due to their feather-like limbs. But what do they use these limbs for? What else can we find out about these odd-looking echinoderms?
Image Source - Imgr
Physical Description and Behavior
The feather star comprises up to 550 different species of crinoids. These invertebrates are echinoderms. The most famous of echinoderms are starfish. They can have many arms. Some can have up to 150 arms. These arms are long and covered with "feather-like" structures which allow them to be able to swim short distances. Visually, they look like walking plants.
After they have found a sponge or coral, they will sit on top and let their feet drift, creating a filter net. This allows floating microorganisms to be caught on their sticky feet. Since they have no true stomach, the food they eat goes straight from the esophagus into the intestines. After being digested, the remaining debris turns into the dense fecal matter which falls to the ocean floor.
Fun fact: A lot of the warm sand that you feel on beaches are actually fish poop. Fish poop and carcasses that biodegrade make up a significant amount of the surface of a beach, so think about that next time you go swimming.
Habitat and Location
The strange thing about these feather stars is the fact that they seem to fare better in warmer temperatures. Studies have shown that they can regenerate lost limbs faster when water is warmer. This means that feather stars are one of the few sea animals that may benefit from rising sea temperatures.
While these feather stars are found in most areas of the world, they seem to be more biodiverse in the coasts of the US, as well as on both sides of the Atlantic Ocean. Australia with its coral reefs is well known as a hotspot for these aquatic animals.
Learn more about these amazing sea stars by watching the video below: